The goals of the Clinical Core are (1) to recruit and thoroughly evaluate persons with Alzheimer's disease and unaffected individuals, (2) to determine eligibility for and distribute appropriate participants to the two proposed clinical projects, and (3) to follow a subset of these persons who agree to brain autopsy with annual re-evaluations to assure timely assessment of clinical status proximate to death for the three proposed clinical-pathologic projects. The ability of Clinical Core to meet these goals, will be greatly facilitated by the Clinical and Religious orders Study. The ability of Clinical Core to meet these goals, will be greatly facilitated by the Clinical and Religious orders Study (ROS) Cores of the existing Rush ADCC. Specifically, since March 2, 1992, these two cores of the Rush ADCC have evaluated 2217 persons. The clinical evaluations are uniform and structured and the diagnosis of probable AD conforms to the recommendations of the NINCDS/ADRDA Workgroup. The Rush ADCC is staffed by skilled neurologists and neuropsychologists with extensive experience in the evaluation of persons with dementia, and a supporting staff skilled in adapting evaluations to the needs of the patients, their families, and friends, and coordinating multiple studies.